Laurence Payne wrote:
On Sat, 16 Sep 2006 23:10:04 GMT, Uncopyrightable wrote:

ok, i don't get it.. I get the bit about use cheap cables, you all say
the same, what I don't get is how companies can get away with selling
£40.00+++ pm cable, when you all reckon go cheap.
If I go cheap is it better to bi-wire? most of the on-line reviews I
have read say bi-wiring is the best way to go, I am now very confuzzed.

I quite agree. How DO they get away with it?

No, you don't need to bi-wire. Period.



They get away with it because cables can sound different.Many expensive
cables are made deliberately to sound different.Not necessarilly
better,but people are easily fooled into believing that different is
better.[which within the context of their system,room acoustics and
hearing could be true]

Many here will maintain that cables do not sound different.Many others
disagree.
You should decide for yourself.Ignore the thought police.

A good way of testing this is to try two sets of cheap cables-one
stranded copper like 79 strand and one 2 core solid copper[house
lighting wiring for example].
To my hearing these cables sound obviously different.If you can hear a
difference that is good.If you can't then that is also good.You should
get a friend to swap the cables over while you listen though[blindfold
listening].
If you do hear a difference though and prefer one type,don't make the
mistake of thinking that price has anything to do with sound quality.In
my experience it certainly doesn't and I have friends with very
expensive systems who use cheap 2 core cable after trying various
expensive cables.

In article om,
wrote:

Laurence Payne wrote:
On Sat, 16 Sep 2006 23:10:04 GMT, Uncopyrightable wrote:

ok, i don't get it.. I get the bit about use cheap cables, you all
say the same, what I don't get is how companies can get away with
selling £40.00+++ pm cable, when you all reckon go cheap. If I go
cheap is it better to bi-wire? most of the on-line reviews I have
read say bi-wiring is the best way to go, I am now very confuzzed.

I quite agree. How DO they get away with it?

No, you don't need to bi-wire. Period.



They get away with it because cables can sound different.

http://www.st-and.demon.co.uk/AudioM.../lscables.html

http://www.st-and.demon.co.uk/AudioM...kracables.html

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html

On Sun, 17 Sep 2006 10:10:53 +0100, Jim Lesurf
wrote:

They get away with it because cables can sound different.

http://www.st-and.demon.co.uk/AudioM.../lscables.html

http://www.st-and.demon.co.uk/AudioM...kracables.html

Those links argue against "audiophile" differences in cables.

"Jim Lesurf" wrote in message
...
In article om,
wrote:

Laurence Payne wrote:
On Sat, 16 Sep 2006 23:10:04 GMT, Uncopyrightable
wrote:

ok, i don't get it.. I get the bit about use cheap cables, you
all
say the same, what I don't get is how companies can get away
with
selling £40.00+++ pm cable, when you all reckon go cheap. If I
go
cheap is it better to bi-wire? most of the on-line reviews I
have
read say bi-wiring is the best way to go, I am now very
confuzzed.

I quite agree. How DO they get away with it?

No, you don't need to bi-wire. Period.



They get away with it because cables can sound different.

http://www.st-and.demon.co.uk/AudioM.../lscables.html

http://www.st-and.demon.co.uk/AudioM...kracables.html

Slainte,

Jim

--
Electronics
http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html


Having read Jim's files with which I have no arguement, there is
another reason for having a very low cable resistance.

When drive ceases to a loudspeaker cone that is not in its rest
position (we're talking here about LF drivers) its suspension tries to
put it back to the rest position. Inevitably it will overshoot a
little and pass the rest position, so it will oscillate slightly but
in reducing amounts until it stops. During this time the coil is
moving in a magnetic field and so the loudspeaker becomes a generator.

There are two basic reasons that an audio amp has a low output
impedence: one is to follow the time-honoured engineering principle
that the source is low impedence driving a high impedence load; the
second is that the amp 'sees' the energy generated by the loudspeaker
as it settles and must dissipate it and in this instance the amp
output impedence is the load. The lower the amp output impedence the
greater the load it will place on the loudspeaker generator and so the
quicker that generator will die.

If you now put cables of significant resistance in series between the
amp and the loudspeaker-generator the load imposed on the generator
will be reduced and it will take longer to come to rest. The effect of
this is quite audible - the bass tends to sound indistinct and a tad
unreal - 'flappy' or 'flabby' are the usual words. It is thus fairly
safe to say that the larger the loudspeaker cone and the louder you
want to play it, the thicker the cables should be.

Incidently the ratio of the amp output design load - typically 8R - to
the amp output impedence is known as the damping factor. It is normal
to expect a damping factor of at the very least 40 (indicating an amp
output impedence of 0.2R) and more usually 60-80. It can be argued
that going much above this will cause other undesirable effects as
reduction of the output impedence of the amp is often achieved by use
of negative feedback in the amp design which can itself cause audible
artifacts.


--
Woody

harrogate3 at ntlworld dot com

harrogate3 wrote:

It can be argued
that going much above this will cause other undesirable effects as
reduction of the output impedence of the amp is often achieved by use
of negative feedback in the amp design which can itself cause audible
artifacts.

How does negative feedback cause these 'audible artifacts' ?

It's yet another one of those silly myths based on more junk science !

Graham

"harrogate3"

If you now put cables of significant resistance in series between the
amp and the loudspeaker-generator the load imposed on the generator
will be reduced and it will take longer to come to rest. The effect of
this is quite audible - the bass tends to sound indistinct and a tad
unreal - 'flappy' or 'flabby' are the usual words. It is thus fairly
safe to say that the larger the loudspeaker cone and the louder you
want to play it, the thicker the cables should be.


** What ******** - amplifier damping does not relate to cone size or
playing level.

It relates only to the DC resistance of the speaker in use.

The FACT is that connecting cable resistance has barely ANY effect on
speaker damping - since it is in SERIES with the resistance of the
voice coil of the speaker.

The resistance of typical bass speakers is 7 ohms - which INCREASES at
high power levels to possibly 12 ohms or more !!

This increase has the SAME EFFECT on damping as using speaker cables with
** 5 ohms ** resistance !!

Purely due to the temperature coefficient of resistance of copper wire.

Not a single thing you can do about that, short of going to planar or full
range electrostatic designs.


Incidently the ratio of the amp output design load - typically 8R - to
the amp output impedence is known as the damping factor.


** But has NOTHING to do with **electrical damping** as experienced by a
woofer.

Because its own *temperature dependant* resistance IS the DOMINANT factor
in the damping equation.


( Snip even more and worse drivel that must have come from some crackpot's
web site or audiophool rag.)



........ Phil

In article , harrogate3
wrote:

"Jim Lesurf" wrote in message
...


http://www.st-and.demon.co.uk/AudioM.../lscables.html

http://www.st-and.demon.co.uk/AudioM...kracables.html


Having read Jim's files with which I have no arguement, there is another
reason for having a very low cable resistance.

When drive ceases to a loudspeaker cone that is not in its rest position
(we're talking here about LF drivers) its suspension tries to put it
back to the rest position. Inevitably it will overshoot a little and
pass the rest position, so it will oscillate slightly but in reducing
amounts until it stops. During this time the coil is moving in a
magnetic field and so the loudspeaker becomes a generator.

That is actually included and implicit in the standard argument based on
the input impedance as a function of frequency. It follows from linear
superposition and that the pattern in time is directly related to the
complex frequency response.

There are two basic reasons that an audio amp has a low output
impedence: one is to follow the time-honoured engineering principle that
the source is low impedence driving a high impedence load; the second is
that the amp 'sees' the energy generated by the loudspeaker as it
settles and must dissipate it and in this instance the amp output
impedence is the load. The lower the amp output impedence the greater
the load it will place on the loudspeaker generator and so the quicker
that generator will die.

There is generally an internal series resistance in the speaker system.
This will tend to have a resistance value which is much higher than that of
the cable or most amplifiers. Thus the effect on what people call 'damping'
is generally dominated by this in practice - unless the cables or amp have
'large' impedances - e.g. of the order of an Ohm or more.

If you now put cables of significant resistance in series between the
amp and the loudspeaker-generator the load imposed on the generator will
be reduced and it will take longer to come to rest. The effect of this
is quite audible - the bass tends to sound indistinct and a tad unreal -
'flappy' or 'flabby' are the usual words. It is thus fairly safe to say
that the larger the loudspeaker cone and the louder you want to play it,
the thicker the cables should be.

Incidently the ratio of the amp output design load - typically 8R - to
the amp output impedence is known as the damping factor. It is normal to
expect a damping factor of at the very least 40 (indicating an amp
output impedence of 0.2R) and more usually 60-80. It can be argued that
going much above this will cause other undesirable effects as reduction
of the output impedence of the amp is often achieved by use of negative
feedback in the amp design which can itself cause audible artifacts.

"Damping factor" as quoted in amplifier specs is a bit of a misleading term
for the reasons given above. In reality, the level of motion damping will
tend to be dominated by the internal series resistance of the speaker
system itself.

IIRC Briggs and others showed this both by theory and by measurement about
45 years ago.

Slainte,

Jim

--
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Audio Misc http://www.st-and.demon.co.uk/AudioMisc/index.html
Armstrong Audio http://www.st-and.demon.co.uk/Audio/armstrong.html
Barbirolli Soc. http://www.st-and.demon.co.uk/JBSoc/JBSoc.html